Increasing number of outgoing connections

Question

We have a cluster of window services that acts as a "hub". These services will consume a number of 3rd party web services. Currently we have maxConnection set to 20. However, there are times when the services are handling more then 20 concurrent requests each and any calls to external web services will be dropped.

Is there anything we need to look out for if we increase this number? What would be the maximum number that we can set safely?

<system.net>
    <connectionManagement>
        <add address="*" maxconnection="20" />
    </connectionManagement>
</system.net>

Edit: Due to the nature of the system, we cannot use queues to management the requests.

Answer 1

Microsoft recommends 12 * n where n is the number of processors, however you should consider configuring more parameters. This KB article is a good starting point:

http://support.microsoft.com/kb/821268